Carrageenan is a linear-sulfated polysaccharide of D-galactose and 3,6 anhydro-D-galactose (3.6 AG) which is extracted from red seaweed (Rhodophyceae). Commercially available carrageenans are essentially ground, dehydrated gels containing approximately 12% water. These materials can viscosity or gel a system into which they are incorporated. Rheological properties of the carrageenan depend upon the nature and quantity of the carrageenan, as well as the inclusion of other components (particularly salts and polyols) in the formulation.
Carrageenan has been used as a toothpaste binder, but its application is limited due to the fact that the cost of this ingredient is relatively high as compared with alternative binders. For example, CMC (carboxymethyl cellulose) is a reagent which can be used instead of carrageenan as a toothpaste binder. In bulk, the cost of CMC is less than 1/2 the cost of the carrageenan reagent.
In tropical areas, however, a cellulase enzyme attacks CMC. This results in an undesirable decrease in the viscosity of the toothpaste which can become watery. Thus, in tropical countries, particularly those referred to as developing countries, toothpaste producers are forced to use the more expensive carrageenan binding reagent, or an equally expensive alternative such as xanthan, or run the danger of offering the consumer an inferior product. A less expensive alternative to carrageenan as a toothpaste binder which is not subject to the viscosity breakdown of CMC is highly desirable to the producers of toothpaste.